> Much more significant is the 12 dB reduction in the "shrill and annoying" frequency range. Those higher frequencies travel farther than the lower frequencies

> Much more significant is the 12 dB reduction in the "shrill and annoying" frequency range. Those higher frequencies travel farther than the lower frequencies, so cutting them has a bigger perceived effect (and this is all about perceived effect, I believe, not the health effects of the operator). Just agreeing with you that acoustics is complicated and non unidimensional.